Every weekend, when my daughter takes her nap, my son and I enjoy a little time together.

Sometimes I read a book to him.

Sometimes Jack, 4, reads one to me – slowly, carefully and with lots of help every time he says, “You say it.”

He does puzzles while I read my own book. Or we play some of the games we have. Once he drew pictures on construction paper and told me what to write, and we made a little book about “Robots and zookeepers” for his dad. (The only difference between the two is that robots have more eyes.)

We monitor the shows Jack and Viv, 2, watch, and try to limit screen time to a show after breakfast on the weekends and one while I make dinner. They still love “Dora,” and “Wonder Pets” and all the Leap Frog learning shows on Netflix. And occasionally I’ll let them watch the hour-long, horribly dull “Thomas” shows. We don’t have cable, so they only watch shows online and so far haven’t seen commercials.

Viv already likes to hit me and Jack likes to push her, so it’s not like we need to introduce any violent media into their lives. Little kids are naughty enough, right?

Sometimes during those quiet afternoons with Jack, I let him play with the iPad. It’s a big treat – and he likes to play “Monkey Lunch Box,” which is a game of making matches and solving puzzles. Or “Monsters Get Sick,” some storytelling thing I barely understand. Most recently, I downloaded “Fruit Ninja” for him – a game where you swipe flying fruit and splatter it. But sometimes bombs come up and you have to avoid them.

“What are those things?” Jack asked me this past weekend when the bombs appeared on the screen. I didn’t really know how to answer. I didn’t feel like explaining what a bomb is – this question came less than a week after we were in Boston for a family reunion and I crossed the finish line of the marathon minutes before two real bombs went off. We didn’t tell the kids what happened that day, and avoided having any television or radio on when they are awake and refuse to discuss it in their presence.

Ages 2 and 4 are too young to know about that if they don’t have to.

So I waited a beat, and he said, “Are they lanterns?”

“Yes,” I said, relieved. “Don’t smash the lanterns. Just the fruit.”

I feel bad lying about it – mostly because I hate poor vocabulary and don’t want him to use the wrong words for things. It’s the same reason we use the real name for all body parts.

I don’t know what the right thing to do is. And I don’t know why the creators of Fruit Ninja had to throw bombs in it. Wouldn’t snakes or something have been equally fine? I can’t stand how even little bits of needless violence creep into life.

Jack just started being able to read very simple words and books. We have stuck to the “Dear Dragon” series, which is so, so basic and benign. “Yes, mother, I will help make cookies,” that kind of thing. But he picked up a Batman early reader recently, and I couldn’t talk him out of it.

Even though the book was geared toward preschoolers, it was still way, way too violent for me. Thankfully it was also a little too difficult for him, so I read it to him. Which meant in my version there was no evil person, just some guy Batman wanted to help and then they all went swimming (I left out the part about swimming in a sewer to escape the bad guys). Of course, then I had to carefully explain to Philip what the revised version of the book was, for when he read it to him. He’s on board with keeping the kids innocent, which makes me happy. Raising kids is hard enough, without disagreeing about something like that.

It’s funny how strongly I feel about all this. I have three older sisters, and they always let me watch stuff way, way too old for me. Including “Blue Lagoon,” “Grease” and many episodes of “General Hospital.”

I’m grateful my kids were with their aunt hours north of Boston when the bombs went off on April 15. And I’m grateful that my sister kept the television off until they went to bed, even though she was desperate for news. In moments like that, Twitter is heaven – you can get what you want without the kids seeing it.

I know we can’t protect Jack and Viv forever. But we’re going to keep trying.